Transistors typically include gate stacks, gate spacers on the sidewalls of the gate stacks, and source and drain regions on the opposite sides of the gate stacks. The formation of the gate spacers typically includes forming a blanket dielectric layer on the top surface and the sidewalls of the gate stacks, and then performing an anisotropic etch to remove the horizontal portions of the blanket dielectric layer. The remaining vertical portions of the blanket dielectric layer are gate spacers.